Medical grade AC/DC power supplies are quiet
Designed with BF (body floating) -ready isolation and low acoustic noise, the 1U high MU4 series of AC/DC modular power supplies are suitable for test and medical applications where audible disturbances need to be kept to a minimum.
The modular MU4 can provide up to five isolated and regulated outputs and deliver up to 800W. All models in the series feature full MOPP (means of patient protection) isolation, including output to earth, to simplify implementation into BF-rated medical applications. The power supplies can also be used in dental, test and measurement, broadcast, professional audio and industrial equipment.
The power supplies also include intelligent fan control, which means the MU4 fan rotation speed is reduced, producing audible noise down to as low as 36dBA, said TDK-Lambda. A microcontroller algorithm monitors the temperature of the primary converter and each output module, allowing the fan speed to be adjusted for optimum cooling.
The low profile, 1U high, MU4 measures just 89 x 41 x 257.5mm making it suitable for smaller system enclosures.
Initially, nine modules are available, with a continuous range of voltages from 3.3V to 104V and ratings from 150W to 480W. Options include a 5V / 2A standby voltage, fan fail signal, inhibit and enable (for individual or all outputs), DC good, PMBus communication and current share for parallel configurations.
Efficiencies are up to 90 per cent and the MU4 series operates over 85 to 264V AC input, providing 800W at 180 to 264V AC and 600W at 90 to 180V AC input, derating applies below 90V AC. The maximum leakage current is 300 microA – including all tolerances – and the touch current is less than 100 microA. Operating temperature range is ambient temperatures of -20 to +70 degrees C, derating linearly to 50 per cent load above 50 degrees C.
The MU4 series has an input to output isolation of 4,000V AC (2 x MOPP), an input to earth isolation of 1,500V AC (1 x MOPP) and an output to earth isolation of 1,500V AC (1 x MOPP) for suitability in B- and BF-rated medical equipment.
Safety certification is to IEC/EN 60601-1, ES 60601-1. IEC/EN/CSA/UL 62368-1, (IEC/EN 61010-1 designed to meet) and the power supplies are CE / UKCA marked to the Low Voltage, EMC and RoHS EU Directives and UK regulations.
All models also meet EN 55011-B, EN 55032-B radiated and conducted emissions and comply with the EN 60601-1-2:2015 (Edition 4) and EN 61000-4 immunity standards.
The company’s online Quick Product Finder automatically produces an optimised module selection from a wide range of options to make configuration and selection simpler. When the user enters desired output voltages and currents, the Finder automatically produces a seven-digit code with which to place the order.